The Preparation and Properties of Low-Nitrogen Nitrocellulose by Alkaline Denitration

Abstract

Waste high-nitrogen nitrocellulose (NC) has always been disposed of as hazardous material for destruction, and has not been recycled as a resource. The present work describes how waste high-nitrogen NC may be converted to low-nitrogen NC via an alkaline denitration reaction between sodium hydrosulfide and the nitrate ester groups, in order to control and reduce the nitrogen content for industrial products. Scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance spectroscopy (1H NMR) and X-ray diffraction (XRD) were used to detected the changes in the surface morphology and chemical structure of the NC samples. TG-DSC tests analyzed the decomposition temperature and the heat released on thermal decomposition, and the explosion heat was obtained by calorimetry. The results demonstrated that the denitration reaction does not destroy the skeletal structure of NC. Notably, the nitrogen content of NC may be reduced from 12.92 to 10.74%, generating the level for industrial products (N <12%). Moreover, NC samples with different nitrogen contents have similar decomposition trends and decomposition temperatures, but the heat released is gradually decreased and the explosion heat is significantly reduced, and confirms the successful partial removal of nitrate ester groups from NC. Therefore, the alkaline denitration affords a potential method for recycling waste high-nitrogen NC.